It seems to be the day for responses and this one is rather long and quotes ALOT of statistics that will take a while to digest and go through but the email goes like this:
I am going to request copies of the reports they had found, just to make them do some work at the very least. At least this report shouldnt cost $120 to get a copy.
Cheers
Ben
Benjamin
In response to your E-Mail of January 7th, 2008 I provide the following comments.
Firstly it is unfortunate that another motorcyclist has lost their life on the road network.
There are a number of mis-conceptions regarding road safety barriers and in particular of wire rope barrier and I have put together a number of bullet points below which deal with the ones more commonly raised about these issues.
Before listing these you may be aware that Main Roads has had meetings with the Motorcycle Riders Association of WA about motorcyclists and road safety barriers and a project is currently underway in which protective treatments for wire rope barriers is being investigated. However, there are limitations to these protective treatments which is explained in detail below.
· Ideally all roads would have a clear zone in all directions to allow errant vehicles to come to a relatively safe stop. (Note the clear zone is a function of vehicle speed, number of vehicles and the road geometry.) In practice this is not always possible and under certain circumstances, safety barriers are installed to minimise the risk to all road users.
· Barriers themselves are a hazard, but they are only installed where the overall risk of not installing them is higher than the consequences of a collision with the hazard that they are installed to protect e.g. roadside objects or oncoming traffic.
· The incidence of motorcyclists hitting safety barriers is a very small part of the total motorcycle crash problem and is an even smaller part of the total overall vehicle crash problem.
· Unfortunately there are some recent examples in WA of motorcyclists being killed or severely injured after colliding with W-Beam barriers.
· A 2006 study by Monash University Accident Research Centre (Report No. 260 Intelligent Transport Systems and Motorcycle Safety) found that for motorcycle crashes in Victoria for the five year period January 2000-December 2004 that 60.7% of all fatal motorcyclist crashes and 53.6% of all serious crashes involved on-road crashes. Off-road crashes (of which only a small percentage would involve a barrier) were 42.3 % fatalities and 54.2 % serious injuries.
· The study titled “Motorcycle Impacts To Roadside Barriers – Real World Accident Studies, Crash Tests and Simulations Carried Out in Germany and Australia 2005” revealed that the risk for motorcyclists of being injured when colliding with either a wire rope or a concrete barrier will be high.
· Wire rope safety barriers generally have superior performance or containment characteristics to other barrier types in most situations. This point is supported by the president of the Tasmanian Motorcycle Council, Mr Shaun Lennard who was quoted in the Mercury Newspaper on 6 September 2006 as saying “Although we're not particularly excited about a proliferation of wire ropes, we understand and accept that in many situations it is the best application.”
· Wire rope barriers are only one of the types of road safety barriers used by Main Roads Western Australia.
· Road safety barriers before they are approved for use are crash tested and are evaluated in three areas to ensure that they will perform the necessary role of protecting vehicle occupants. Currently there is no agreed method (in the world) for assessing the performance of road safety barriers for motorcyclists.
· The areas are:
1. Structural adequacy
2. Vehicle trajectory
3. Occupant risk (this deals with detached elements penetrating the vehicle and forces that the vehicle occupant is subjected to so that the crash is survivable)
1. Structural adequacy
2. Vehicle trajectory
3. Occupant risk (this deals with detached elements penetrating the vehicle and forces that the vehicle occupant is subjected to so that the crash is survivable)
· Unlike cars (and trucks) there is no standard test for assessing the relative safety of road safety barrier systems for motorcyclists. Some testing has been undertaken in Europe with the motorcyclist impacting at differing angles and typically has the motorcyclist sliding into the barrier (this is a different scenario to that found in the recent APROSYS work outlined below). What testing has been undertaken for motorcyclists is for 60 km/h.
· A March 2006 report by APROSYS – Integrated Project on Advanced Protection Systems (http://www.aprosys.com/Documents/del...P_SP4_0003.pdf) which investigates motorcyclists crashes with barrier contains the following statement in relation to motorcyclists and barriers:
“Four in-depth accident databases were analysed focusing on infrastructure involvement. The amount of data available for this analysis was rather small. Roadside-barrier impacts occurred under small angles at high speeds, and more often in upright position rather than sliding on the ground. These impacts most caused injuries to the head and lower extremities. There are indications of trees and poles being even more hazardous to PTW (powered two wheel vehicles) riders when being hit.”
· Within Europe a number of products have been developed that would appear to improve the safety of barriers for motorcyclists but it is not clear how these products will affect the performance of the system for other users and at what speed they can offer protection for a motorcyclists. They have been tested for 60 km/h but there is conjecture if they will change the outcome of a crash at speeds in excess of 70 km if the motorcyclist hits in the area of head, neck or chest.
· The Australian Standard for Road Safety Barrier AS 3845 (which contains the requirement for crash testing of barriers) is currently under review and Main Roads as well as Mr Brian Wood from the Australian Motorcycle Council is on the committee. The issue of motorcyclist safety and road safety barriers is one of the topics for consideration by the committee.
· Products that can be demonstrated to reduce motorcyclist injuries (whilst not reducing the effectiveness of the system for other users) would be used where the risk of a collision by a motorcyclist is high (i.e. larger number of motorcyclists on the road or where there is specific road geometry that would increase the likelihood of a crash).
· Whilst wire rope barriers are the cheapest in terms of the initial supply cost this is not the overriding reason they are used. In terms of the safety of vehicle occupants they provide the lowest occupant risk compared to other barrier types and they have the ability to contain and redirect vehicles much greater in mass than what they have been crash tested to.
· Whilst during an impact a longer length of wire rope barrier is damaged than other barrier types such as W-Beam or Thrie Beam they are more quickly repaired than other barrier types (with the exception of concrete barriers which typically require no maintenance after impact).
I am happy to forward to you copies of reports referred to in this E-Mail if this is of interest to you.
Regards
Mr Jan Karpinski
Strategic Asset Manager Engineer
Main Roads Western Australia
Strategic Asset Manager Engineer
Main Roads Western Australia
Cheers
Ben
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